This application is based on Japanese Patent Application Nos. 2008-283150 and 2008-283154 both filed with the Japan Patent Office on Nov. 4, 2008, the entire content of which is hereby incorporated by reference.
1. Technical Field
The present invention relates to a method of creating a three-dimensional model of an object to perform a process of recognizing the position and the orientation of the object using three-dimensional information restored by stereo measurement using a plurality of cameras with an object having a predetermined shape as a target. The present invention also relates to a device for performing, after creating and registering the three-dimensional model, a recognition process of the object using the model.
2. Related Art
A three-dimensional model containing three-dimensional information of various surfaces of an object to be recognized needs to be created to recognize the position and the orientation of the object by a three-dimensional recognition process using a stereo camera.
Japanese Patent Publication No. 2961264 (see paragraphs 0013, 0017, 0028 to 0036) discloses the invention having the above problems. Japanese Patent Publication No. 2961264 describes creating a geometric model of the entire object by performing the stereo measurement from a plurality of directions with respect to an actual model of a target object to be recognized and aligning and integrating three-dimensional information restored by each measurement.
Japanese Patent Publication No. 2961264 also describes restoring three-dimensional information of a contour line of the actual model from an edge shown in the stereo image through a method called “segment based stereo”. According to Japanese Patent Publication No. 2961264, the “segment based stereo” is a process of dividing the edge in the stereo image into units called a “segment”, and performing a stereo correspondence search in units of segments to restore the three-dimensional information of the contour line.
Furthermore, Japanese Patent Publication No. 2961264 describes a method of rotating an actual model to a defined angle using a rotary table and performing a coordinate transformation based on the rotational angle with respect to alignment of the three-dimensional information. As a method of aligning the three-dimensional information from an unknown observation direction, obtaining candidates of a plurality of alignments by matching the model being created and the newly restored three-dimensional contour line, and specifying the alignment when a coincidence degree becomes the highest are also described.
“Stereo Correspondence Using Segment Connectivity” Information Processing Society of Japan, Vol. 40, No. 8, pp. 3219-3229, published August 1999 describes in detail a method of corresponding the two-dimensional segment between images, and restoring the three-dimensional information. “Three-Dimensional Object Recognition Using Stereo Vision” IEICE Transactions, D-11, vol. J80-D-II, No. 5, pp. 1105-1112, published May 1997 discloses a method of matching the restored three-dimensional information with the three-dimensional model registered in advance, and recognizing the position and the orientation of the object.